The present invention relates to an oil pan, in particular for an internal combustion engine, with a drain mechanism adjustable between open and closed positions.
Oil pans of this type, which are arranged on the underside of an internal combustion engine, must be designed to be stable to withstand high forces, to also withstand high mechanical influences which may occur, for example, from a stone strike or from the vehicle scraping the ground. Also known are oil pan embodiments made of metal or even a one-piece injection-molded part made of polyamide or polypropylene, as described in published European patent application no. EP 1,041,253. To be able to drain the oil out of the oil pan, a drain opening, which can be closed by an adjustable closing element, is provided in the bottom of the pan. In oil pans made of metal, this closing element may be constructed as an oil drain screw which is screwed into the drain opening under pressure via a copper gasket, so that a leak-proof condition is established. In oil pans made of synthetic resin material, a screw connection of the oil drain screw to the wall of the oil pan is problematic for strength reasons. Instead, threaded inserts may be used, which are inserted into the opening to be sealed. However, this is associated with a relatively great complexity and cost; Furthermore, there is a risk that the threaded insert may be ripped out if it is subjected to too much force.